RESEARCH PEARL - Chondroitin Sulfate Diminishes Neuropathic Pain

CHONDROITIN SULFATE ATTENUATES SCIATIC NERVE INDUCED NEUROPATHIC PAIN BY INHIBITING SPINAL P38 MSPK PHOSPHORYLATION AND A BETA FIBER ACTIVATION. CHONDROITIN SULFATE (CS) IS A COMPOUND USED TO TREAT OSTEOARTHRITIS AND JOINT PAIN. REPEATED ORAL ADMINISTRATION OF CS (300 MG/KG, B.I.D. FOR 20 DAYS) RESULTED IN INHIBITION OF TACTILE ALLODYNIA OBSERVED 21 DAYS AFTER PSNL. ON DAY 21, PHOSPHORYLATION OF SPINAL P38 MITOGEN-ACTIVATED PROTEIN KINASE (MAPK) WAS ATTENUATED BY CS. CS ALSO INHIBITED C-FOS UPREGULATION IN IPSILATERAL DEEP DORSAL HORN (LAMINAE III-IV) NEURONS, WHICH RECEIVE AΒ-FIBER AFFERENT INPUTS. THESE FINDINGS SUGGEST THAT CS ATTENUATES PSNL-INDUCED TACTILE ALLODYNIA BY INHIBITING SPINAL P38 MAPK PHOSPHORYLATION AND AΒ-FIBER ACTIVATION.

NOTE: phosphorylation defined

Phosphorylation - the process of introducing a phosphate group into an organic molecule.

• oxidative phosphorylation the final common pathway of aerobic energy metabolism in which high-energy phosphate bonds are formed by phosphorylation of ADP to ATP coupled with the transfer of electrons along a chain of carrier proteins with molecular oxygen as the final acceptor. It occurs in mitochondria.
• Miller-Keane Encyclopedia and Dictionary of Medicine, Nursing, and Allied Health, Seventh Edition. © 2003 by Saunders, an imprint of Elsevier, Inc. All rights reserved.

phos·phor·y·la·tion -  (fos'fōr-i-lā'shŭn) - Addition of phosphate to an organic compound, such as glucose to produce glucose monophosphate, through the action of a phosphotransferase (phosphorylase) or kinase.

• Farlex Partner Medical Dictionary © Farlex 2012

phosphorylation -  /phos·phor·y·la·tion/ (fos-for″ĭ-la´shun) the metabolic process of introducing a phosphategroup into an organic molecule.

• oxidative phosphorylation - The formation of high-energy phosphate bonds by phosphorylation of ADP to ATP coupled tothe transfer of electrons from reduced coenzymes to molecular oxygen via the electron transport chain; it occurs in the mitochondria.
• substrate-level phosphorylation - The formation of high-energy phosphate bonds by phosphorylation of ADP to ATP (orGDP to GTP) coupled to cleavage of a high-energy metabolic intermediate.
• Dorland's Medical Dictionary for Health Consumers. © 2007 by Saunders, an imprint of Elsevier, Inc. All rights reserved

phosphorylation - [fosfôr′ilā′shən] - the process of attaching a phosphate group to a protein, sugar, or other compound.

• Mosby's Medical Dictionary, 9th edition. © 2009, Elsevier.

Nemoto W1, Yamada K2, Nakagawasai O3, Ogata Y3, Chiba M3, Yamagata R3, Sakurai H2, Tan-No K3. Effect of repeated oral administration of chondroitin sulfate on neuropathic pain induced by partial sciatic nerve ligation in mice. J Pharmacol Sci. 2018 Mar 23. pii: S1347-8613(18)30047-1. doi: 10.1016/j.jphs.2018.03.003. [Epub ahead of print]

Researchers examined whether chondroitin sulfate (CS), a compound used to treat osteoarthritis and joint pain, is effective against partial sciatic nerve ligation (PSNL)-induced neuropathic pain. Repeated oral administration of CS (300 mg/kg, b.i.d. for 20 days) resulted in inhibition of tactile allodynia observed 21 days after PSNL. On day 21, phosphorylation of spinal p38 mitogen-activated protein kinase (MAPK) was attenuated by CS. CS also inhibited c-Fos upregulation in ipsilateral deep dorsal horn (laminae III-IV) neurons, which receive Aβ-fiber afferent inputs. These findings suggest that CS attenuates PSNL-induced tactile allodynia by inhibiting spinal p38 MAPK phosphorylation and Aβ-fiber activation.